Possible TDB/Samba optimizations.

[COLLOT Jean-Yves]

> Connections is one that I would want to move to use the LOCKING code. 
> Connections must be removed from the table if a SMBD process crashed.

Removal of old connections from crashed SMBD processes is now done : when a
new connection comes in, all connections in the TDB file that is owned by
non existent processes are removed.

> I think that there is a way to have more bytes than that associated with 
> a lock.  It would take some research.  Possibly sublocks.

As an example, the TDB record for a connection is 604 bytes long. For the
LOCKING TDB file, it is 145 bytes long.